This Atlas represents the first 500 years of Christianity and can thus, for the most part, safely rely on ethnic and national boundaries to provide the basic context for the maps and drawings that illustrate change.

Three main areas are emphasized:

theology and dogma;

ethical and moral life;

and the early phase of the expansion of Christianity to a world religion.

The Rev. Franklin H. Littell (1915–2009), a Methodist minister, was emeritus professor of Religion at Temple University in Philadelphia and a longtime adjunct professor at The Hebrew University of Jerusalem. He dedicated his life to Holocaust research after spending nearly 10 years in postwar Germany as chief Protestant religious adviser in the U.S. High Command. He was the author of more than two dozen books, including The Crucifixion of the Jews, The German Phoenix, and Religious Liberties in the Crossfire of Creeds, and more than 1,000 articles.